1. Technical Field
The technology disclosed herein relates to an interchangeable lens type of camera system, camera body, and lens unit with which lenses can be interchanged.
2. Background Information
Recent years have witnessed the growing popularity of digital cameras in which a CCD (charge-coupled device) image sensor, a CMOS (complementary metal oxide semiconductor) image sensor, or another such imaging element is used to convert a subject image into an electrical image, and this electrical signal is digitized and recorded (see International Laid-Open Patent Application 2009/041063).
With interchangeable lens cameras, such as digital single-lens reflex cameras or digital range finder cameras, there has been a need to achieve high-speed and highly accurate focusing and to correct lens aberration on the camera side, in order to accommodate the reduction in the size of pixels resulting from an increase in the number of pixels of an imaging element and viewing in the situations in which images are highly enlarged on a computer screen, and so forth. Also, high-resolution moving picture capture is also possible, and high-precision lens control has become essential.
However, the zooming interchangeable lenses made up to now whose purpose was the capture of still pictures involved rotary optical zooming by hand, or rectilinear optical zooming by hand, so a problem was that it was difficult to perform smooth zooming or zooming at a constant rate during moving picture capture. Therefore, there has been a need for electrical optical zooming with a zooming interchangeable lens.